Electric plug



April 6, 1937. E WEED 2,076,136

ELEGTRI C PLUG Filed Jan. 5, 1936 Invenlor zg/wm E Med 6 A llomeysPatented Apr. 6, 1937 UNlTED STATES PATENT GFFHIE 3 Claims.

This invention appertains to new and useful improvements in electricplugs, the same being an improvement on my co-pending application 6. N.720,325 filed April 12, 193 i.

The principal object of the present invention is to provide an automaticcut-out plug which in operation will be substantially automatic in allrespects.

Another important object of the invention is 10 to provide 21. out utplug of the character stated which will eliminate all manual tension.

Other important objects and advantages of the invention will becomeapparent to the reader of the following specification.

In the drawing:

Figure 1 represents a longitudinal sectional view through the plug.

Figure 2 represents an end elevational view of the plunger.

I Referring the drawing wherein like numerals designate like parts, itcan be seen that numeral 5 represents a dielectric casing provided withthe end wall "I and the plug 8 engaged into and secured to the oppositeend oi the shell.

95 The end wall 1 is provided with an opening 9 therein through whichthe plunger stem It is slidable. This stem I is slidable through theelectro-magnetic coil H and is provided with a bore I2 extendinginwardly of its inner end for receiving a substantial portion of thecoiled compressible spring E3. The other end of the spring I3 engagesinto a recess in one side of the dielectric partition 14 which crossesthe inside of the shell and supports the two bind-- ing posts l5--l6. Ajumper between the post l5 and the coil H is denoted by numeral ll,

While a jumper l8 extending through the wall of the shell 5 extends fromthe binding post or screw H to the prongs on. the end wall I.

The prong H is connected as at 22 to the other side of the coil ll.

A slot is provided in the bridge plate 23 through which the stem i0 isslidable. A spring yoke 24 in this slot engages the stem Ill andfrictionally holds the bridge plate 23 to the stem ID. The opposite endof the stem l0 protrudes beyond the end wall I of the shell 5, so thatwhen the prongs 20-2l are engaged with a wall socket or the like, thestem I0 is pushed inwardly and forces the bridge piece 23 to bridge thecontacts Iii-l6. In the event of a short circuit, the coil H becomesenergized sufiiciently to attract the bridge piece 23 which slides onthe stem I0. When the plug is removed from the 55 electrical receptacle,the stem I0 is again projectecl outwardly from the spring it so that thebridge member 2? returns to its proper position on the stem Lil.

While the foregoing specification sets forth the invention in specificterms, it is to be understood that changes in the shape, size andmaterials may be resorted to without departing from the spirit or scopeof the invention as claimed hereinafter.

Having thus described claimed as new is:

1. In an electric plug. an electro-magnet, a pair of contacts spacedlyopposed to one end oi the magnet, an armature adapted to bridge thecontacts and being magnetically responsive to the magnet, a stemextending from the armature and longitudinally of the magnet to projectbeyond the opposite end thereof and adapted to hold the armaturebridging the contacts in re sponse to the application of longitudinallydirected external force, and frictional clutch means constructed andarranged between the armature and the stem whereby the armature canslide on the stem in response to the magnetic force of theelectro-magnet to unbridge the said contacts.

2. In an electric plug, an electro-magnet, a pair of contacts spacedlyopposed to one end of the magnet, an armature adapted to bridge thecontacts and being magnetically responsive to the magnet, a sternextending from the armature and longitudinally of the magnet to pro jectbeyond the opposite end thereof and. adapted to hold the armaturebridging the contaste in response to the application of longitudinallydirected external force, and frictional clutch means constructed andarranged between the armature and the stem whereby the armature canslide on the stem in response to the magnetic force of theelectro-magnet to unbridge the said contacts, and spring means engagedwith the stem normally tending to urge the stem outwardly with thearmature removed from the contacts.

3. In an electric plug, an electrmmagnet, a pair of contacts spacedlyopposed to one end of the magnet, an armature adapted to bridge thecontacts and being magnetically responsive to the magnet, a stemextending from the armature and longitudinally oi the magnet to projectbeyond the opposite ,end thereof and adapted to hold the armaturebridging the contacts in response to the application of longitudinallydirected external force, and frictional clutch means constructed andarranged between the invention, what is ture provided with an openingthrough which the stem is slidably disposed, said spring member beingadapted to tensionally engage the portion of the stem extending throughthe opening of the armature.

EDV/ARD E. WEED.

